British Pat. No. 881,607 relates to a cassette seal of this type. The counterring comprises two angular rings which are joined together to form a U-shaped profile and which are produced by deep-drawing. The fabrication method is extremely cost-effective up to this point, but necessitates the use of deep-drawable materials, i.e., materials which have only relatively small mechanical strength. This may result in premature wear.
In addition, the running surface of deep-drawn angular rings of this type frequently exhibits a waviness which extends in the circumferential direction. When there is a high relative velocity of the sealing lip, this can lead in some regions to a reduction of the contact pressure or to a lifting of the sealing lip, which results in leaks. Elastomer materials with high flexibility are very suitable and are extensively used for making the sealing lip. However, these materials frequently have an adverse wear behavior which shortens the service life considerably.